Stress Cracks

I.N.the.SKY · Jan 21, 2016

Greetings fellow flyers! I have a P3P with 75 flights so far. EVERYTHING has worked to perfection, not one issue to complain about.
I saw a video on youtube about these stress cracks and I've read several of you too have these cracks. The video I saw said the screws are just too tight from the factory and that I could back them out and retighten them correctly. My questions are:
1. Is this actually gonna work?
2. Is there anything I can do besides this to prevent the cracks?
3. What effect, if any, do the cracks have?
4. Exactly why are these cracks happening?

CCDD · Jan 21, 2016

don't fix what's not broken, just leave it be.

msinger · Jan 21, 2016

This is an issue that does not affect most Phantom owners. Therefore, it's not likely it'll happen to you. Some believe the issue is caused by the design of the shell, but DJI has not confirmed this. They have reinforced the shell though. DJI is constantly working on making the Phantom better, so we should not necessarily assume the redesign was put in place solely to resolve this issue. Some people have reinforced the inside of their shell with things like Bondic and/or installed 3rd party reinforcement devices because they believe it'll prevent the shell from cracking. The jury is still out on whether or not any of those things have helped.

tl;dr: DJI will fix this for free if it happens to you.

fvader · Jan 21, 2016

I.N.the.SKY said:
Greetings fellow flyers! I have a P3P with 75 flights so far. EVERYTHING has worked to perfection, not one issue to complain about.
I saw a video on youtube about these stress cracks and I've read several of you too have these cracks. The video I saw said the screws are just too tight from the factory and that I could back them out and retighten them correctly. My questions are:
1. Is this actually gonna work?
2. Is there anything I can do besides this to prevent the cracks?
3. What effect, if any, do the cracks have?
4. Exactly why are these cracks happening?

Can't say i agree with the leave it be comment.
stress cracks are not made up. so you should take measures to prevent them.
if you did nothing and you motor mounts break loose then you'd be upset with yourself.

For me I'm designing and printing pieces that will cover the bottom and end, this will distribute the stress over a wider surface area.

If you don't have access to a printer, you can find them for sale on the net in various places.

fastsmiles · Jan 21, 2016

UAV Bits has the original Strong Arm reinforcement plate. We made the first plates to address this problem and have been making and improving them longer than anyone else. We have several designs for use with different cases and backpacks. The best quality and the greatest selection.

Mike's Bird · Mar 27, 2016

fvader said:
Can't say i agree with the leave it be comment.
stress cracks are not made up. so you should take measures to prevent them.
if you did nothing and you motor mounts break loose then you'd be upset with yourself.

For me I'm designing and printing pieces that will cover the bottom and end, this will distribute the stress over a wider surface area.

If you don't have access to a printer, you can find them for sale on the net in various places.

Agreed, stress cracks are not made up. I have the proof looking at me. No hard landings. No crashes. I had stress cracks in one motor mount and a shell screw hole crack on the outside edge from the screw hole to the edge of the shell. Not major but very concerning. After reading over the blogs, I decided to take the shell apart (a royal pain to do it right) and look inside. The motor mount cracks didn't go through to the inside and no other damage was seen on the other arms. I did do the Bondic routine on all motor mounts to beef up the inside and ordered up a set of StrongArms for the hard shell backpack case.
The one thing I have to say is that the screws mounting the motors and shell case on the arms that were stressed were very, very tight. Noticeably more than the other two arms. Yes, they were held by a lock tight substance but all the screws were. I suspect the over tightened screws weaken the plastic and any added stress (like flying) pushes the plastic beyond it's capability.
Soooo, I'll fly it and watch for additional issues and report back. BTW, I also backed off the brake setting in the DJI Go app as suggested in another string. I would expect the design would match the flight characteristics, but here we all are, trying to figure out solutions to a problem that shouldn't exist.

Az Wing · May 30, 2016

Noticed stress cracks on one arm during a preflight yesterday. Never experienced a hard landing or crash. E-mailed DJI but have not received a response, yet. The P3P is only six months old. How is DJI handling returns/exchanges for this on-going issue these days? I read in the warranty info that shell issues are not covered.

Wibble · May 30, 2016

I think backing off the screws may help BUT if they have been overtightend then you could cause extra damage. I would be inclined to leave them alone. Keep you drone out of direct sunlight as much as you can and do NOT leave in a hot car.

Thunderbyte · May 30, 2016

I found a stress crack on my P3P yesterday. At some point I will likely just replace the shell myself instead of sending it back and waiting for them to fix it. Has anyone ever had a crash or in flight failure caused by the cracks(s)? To me it doesn't look that bad and to be honest I plan to fly a few more weeks until I make time to repair it. I will monitor to make sure it doesn't get worse but honestly it doesn't look like inflight failure is immenent.

bluer101 · May 30, 2016

Thunderbyte said:
I found a stress crack on my P3P yesterday. At some point I will likely just replace the shell myself instead of sending it back and waiting for them to fix it. Has anyone ever had a crash or in flight failure caused by the cracks(s)? To me it doesn't look that bad and to be honest I plan to fly a few more weeks until I make time to repair it. I will monitor to make sure it doesn't get worse but honestly it doesn't look like inflight failure is immenent.

Yes, there has been a few with in flight failures. Strong vibration then total motor separation.

TheLightSpeedz · May 30, 2016

Take those prop guards off. Those are begging for cracks on a P3. You're better off with the removable ones

Sent from my iPhone using PhantomPilots mobile app

Not A Speck Of Cereal · May 30, 2016

I suppose this would be a bad time to mention that I have prop guards for sale ...

SnoozeDoggyDog · May 30, 2016

I've had two p3a over a period of 2 years, sold the first one and then bought another new one 3 days ago. The first one developed cracks and was flown like a baby and always hand caught.... it got cracks about 10 flights in. Needless to say I've backed All the screws off about half a turn on the new one.

Mudcat · May 30, 2016

msinger said:
This is an issue that does not affect most Phantom owners. Therefore, it's not likely it'll happen to you. Some believe the issue is caused by the design of the shell, but DJI has not confirmed this. They have reinforced the shell though. DJI is constantly working on making the Phantom better, so we should not necessarily assume the redesign was put in place solely to resolve this issue. Some people have reinforced the inside of their shell with things like Bondic and/or installed 3rd party reinforcement devices because they believe it'll prevent the shell from cracking. The jury is still out on whether or not any of those things have helped.

tl;dr: DJI will fix this for free if it happens to you.

After reading this I checked my p3p and I have cracks as well. I'm not sure how to send this back to DJI, and also wonder if anyone has, and how long is the turnaround time?

RocketBrew · May 30, 2016

Mudcat said:
After reading this I checked my p3p and I have cracks as well. I'm not sure how to send this back to DJI, and also wonder if anyone has, and how long is the turnaround time?

I just got my first crack after 6 months on W323A version.
Submitted an online support form on DJI.com with all the pertinent info; model #, s/n, DJI order #, purchase date, photos.
Received an email a day later asking for the model #, s/n, DJI order #, purchase date. Replied with requested info.
Received an e-mail with RMA info a couple of days later, including a form to fill out with the model #, s/n, DJI order #, purchase date to include with the return.
Will be shipping it off tomorrow, will see how long the repair and return takes. Have heard it is much better now, maybe because they have better records of the details...

Mudcat · May 31, 2016

msinger said:
This is an issue that does not affect most Phantom owners. Therefore, it's not likely it'll happen to you. Some believe the issue is caused by the design of the shell, but DJI has not confirmed this. They have reinforced the shell though. DJI is constantly working on making the Phantom better, so we should not necessarily assume the redesign was put in place solely to resolve this issue. Some people have reinforced the inside of their shell with things like Bondic and/or installed 3rd party reinforcement devices because they believe it'll prevent the shell from cracking. The jury is still out on whether or not any of those things have helped.

tl;dr: DJI will fix this for free if it happens to you.

I have founds cracks on the outside screw holes on one arm and would like to send it in for repair. Do you know a phone number where I can reach someone to help me with this? I'm finding it hard to contact DJI? I'm really disappointed with this, and hope I can find a quick repair.

greg r e · May 31, 2016

I also developed cracks and had good results with the 5 second plastic welding formula that uses uv light to cure.i sent my bird back for an rc issue, and dji had replaced the shells. Thks dji

MILLER4PRESIDENT2020 · May 31, 2016

Wonder how beneficial/ crazy it would be to put some superglue around some of the common stress areas before cracks start to develop....might add weight but I dont think it would do anything bad. You just cant get it in any of the screw holes or the motor.

mrgoodwrench · May 31, 2016

Mudcat said:
I have founds cracks on the outside screw holes on one arm and would like to send it in for repair. Do you know a phone number where I can reach someone to help me with this? I'm finding it hard to contact DJI? I'm really disappointed with this, and hope I can find a quick repair.

The contact phone number is very clearly listed on their website here (DJI Support - Phantom 3 Professional). Why is it hard to contact them?